Extensible pipe section



Feb. 25, 1941. a. F. RUHL EXTENSIBLE PIPE SECTION Filed April 11, 1940ATTORNEY.

Patented Feb. 25, 1941 UNITED STATES PATEN FFIQE 3 Claims.

This invention relates to stove pipes and aimsto provide an extensiblestove pipe by means of which a length of such pipe may be extended orretracted at will by a very simple manual operation. However, theinvention may also be applied in any or every other field in which itWould be desirable to provide an extensible pipe or tube section(whether cylindrical or rectangular) after the manner of the invention,and the inventor does not Wish to limit the application of the inventionto stove pipes.

As shown in the accompanying drawing and described in detail below, thesimple pressing together of two of the projecting ears on one side ofthe pipe will cause elongation of the pipe, and similar pressingtogether of the opposite two ears will cause contraction of the pipe.The entire extensible pipe is made of only five pieces or sections, andit is apparent that these sections present but a simple problem to themanufacturer. The many uses to which such a pipe could be put are tooobvious to require enumeration.

Referring briefly to the drawing,

Figure 1 is a front elevational view of the pipe section, in elongatedcondition.

Figure 2 is a similar view of the same in retracted condition.

Figure 3 is a cross-sectional view taken on the line 33 of Figure 4.

Figure 4 is a cross-sectional view taken on the line 4-4 of Figure 2.

Figure 5 is a fragmentary elevational view, partly in section and withparts broken away, of the pipe section in retracted condition.

Referring in detail to the drawing, the numeral I9 indicates a unitarycylindrical tube having an outwardly extending equatorial bead II formedintegral therewith. A pair of particylindrically shaped slides I2 and I3each having a peripheral bead I4 and I5, respectively, lie substantiallyflush but slidably against the outer surface of the tube I0, with thebead II registering within the beads I4 and I 5. The bead II thusprovides a track on which the beads I4 and I5 are adapted to slide. Eachof the beads I4 and I5 has, as is apparent, two ends. At its two ends,the bead I4 has outwardly extending lugs or handles I6 and I1,respectively; at its two ends the bead I5 has two similar lugs orhandles I8 and I9, respectively.

Near each vertical edge of each slide I2 and 3, ears 2!] are anchored bymeans of their bases 2| (which are at right angles to the ears) in. theslides, at the position shown, i. e., the slide I3 55 has such an ear 20above the bead I5 and another equidistantly below the bead I5, in avertical line, near the edge I8a of the slide adjacent the handle it. Asimilar pair of ears 20 are similally mounted near the opposite edgeI911 of the slide l3, as shown in Figure 3. The slide I2 is similarlyprovided with a like number of similarly spaced ears 22, i. e., two ears22 near the edge 55a and two near the edge Ila.

A sleeve 23 slidably surrounds the slides I2 and I3 above the beadsI4-I5, and a similar 10 sleeve 24 similarly surrounds the slides belowthe beads I l-I5. The sleeve 23 is provided with four slots, of whichthe two at the front, shown at 25 and 26, incline divergently upward,and the two at the rear, 25a and 26a, incline divergently 15 downward.Likewise, the sleeve 2 4 is provided with two slots 21 and 28 whichincline divergent- 1y downward, at the front, and with two similar slots21a. and 28a, which incline divergently upward, at the rear. The upperears 20 and 22 20 register in the slots 26 and 26a, and 25 and 25a,respectively, and the lower ears 20 and 22 register in the slots 28 and28a, and 21 and 21a, respectively. It is apparent that the ends of theslots 25, 26, 21, 28, 25a, Zta, 21a, and 28a, serve as 25 limit stops tothe axial movement of the sleeves 23 and 24 toward or away from thebeads I l-I5.

The operation of the device is as follows. Assuming that the pipesection is in retracted position, as shown in Figure 2, it is elongatedby 30 grasping the handles I6 and I8 between the fingers of one hand anddrawing them together. As these handles approach each other, they forcethe ears 20 toward the ears 22, both in the sleeves 23 and in that 24.Thus, the slots 25, 26, 35 etc. act as cam surfaces, and as the earsride in the slots they force the sleeves 23 and 24 to be projectedoutward. When fully extended, the handles I6 and I8 lie close to eachother, as shown in Figure 1, and the handles I1 and I9 40 are spreadapart. To retract the pipe section to its original position, the handlesI1 and I9 are grasped and drawn together into the position shown inFigure 4, whence the reverse action takes place and the sleeves 23 and24 are drawn 4 toward each other.

It is to be noted, in Figure 3, that the upper peripheries of the sleeve23, slides l2 and I3, and tube It are slightly bent inward. This is doneso as to provide a friction contact between the various parts to preventthem from slipping owing to their own weight when the section is anydesired extended position.

Obviously, modifications in form and structure may be made withoutdeparting from the spirit and scope of the invention.

I claim:

1. A device of the class described comprising a tube having a peripheralbead extending outward therefrom intermediate its length, a pair ofslides concentric with said tube slidably mounted against the outersurface thereof and having aligned beads formed therein, said tube beadregistering in said slide beads and serving as a track on which saidslide beads are adapted to ride, finger grips on the ends of said slidebeads, a pair of sleeves, each of said sleeves being slidably mounted onone end of the device with its inner surface lying slidably against theouter surfaces of said slides, divergent slots in one of said sleeves,oppositely divergent slots in the other of said sleeves, and ears onsaid slides reg istering in said slots.

2. A device of the class described comprising a tube having a peripheralbead extending outward therefrom intermediate its length, a pair ofslides concentric with said tube slidably mounted against the outersurface thereof and having aligned beads formed therein, said tube beadregistering in said slide beads and serving as a track on which saidslide beads are adapted to ride, finger grips on the ends of said slidebeads,

a pair of sleeves, each of said sleeves being slidably mounted on oneend of the device with its inner surface lying slidably against theouter surfaces of said slides, divergent slots in one of said sleeves,oppositely divergent slots in th other of said sleeves, and ears rigidon said slides registering in said slots, said ears comprisingangle-shaped members each having a base anchored in said slides and aWing portion projecting through the slot.

3. A device of the class described comprising a tube having a peripheralbead extending outward therefrom intermediate its length, a pair ofslides concentric with said tube slidably mounted against the outersurface thereof and having aligned beads formed therein, said tube beadregistering in said slide beads and serving as a track on which saidslide beads are adapted to ride, finger grips on the ends of said-slideheads, a pair of sleeves, each of said sleeves being slidably mounted onone end of the device with its inner surface lying slidably against theouter surfaces of said slides, divergent slots in one of said sleeves,oppositely divergent slots in the other of said sleeves, and members onsaid slides registering in said slots.

GEORGE, F. RUHL.

